GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 2.2 GNGTS 2024 log 10 (pga) = 0.346 I EMS-98 - 0.190 With reference to the definiCon of the 5 damage levels of the EMS-98 scale (Grünthal, 1998), Fig. 2a shows the number of heavy damaged buildings (damage level (D4 + D5) in each census tract). Through remote sensing analysis, the project's colleagues esCmated the percentage of pitched and flat terrace roofs of the buildings. These distribuCons, together with the analysis of AeDes data for the idenCficaCon of building types and their vulnerability, made it possible to idenCfy the distribuCon of roofs in four vulnerability classes (Spence et al., 2005). The distribuCon of buildings with total collapse of the roof due to tephra load – if no cleanup acCon is taken- is shown in Fig 2c, but it is necessary to highlight the very low probability to have such a level of loads. In case of lava flow hazard, the level of risk is independent of the vulnerability of the buildings. For each ISTAT census secCon, the number of buildings damaged by lava is calculated proporConally to the percentage of the secCon's area occupied by the flow (Fig. 2b). Once assessed the damage level of the buildings, the totally collapsed buildings, the unusable one, the number of the possible vicCms or of homeless are calculated in each census secCon. Fig.2 – Damage map of residenCal buildings due to the earthquake, lava and tephra flows scenarios. Damage scenarios due to ash loads, lava flows and earthquakes have been esCmated to road and power systems, too. Tab. 1 illustrates damage to the power system (pylons, medium voltage (MV) and high voltage (HV) substaCons and transformers) reach by lava flow with different probability of invasion, as well as the length of invaded road and number of affected buildings. Tab. 1 – Damage due to the 2018 lava flow scenario POWER SYSTEM Road system ResidenHal